Porpoising Seavette

[lost2a6]

Are any of you guys that have a 23 SC running over 60 MPH? The reason why I ask is because my boat starts porpoising at 60 and then just gets worse the faster that I go. It will even do it with the outdrive all the way down. I can put the tabs down some and it will stop but I would like to get it to run with out using the tabs. I was told by a local prop guy that the hull just wasn't designed to go that fast. I have tried several props with about the same results. I haven't tried a semi cleaver prop yet. I believe that the boat just has too much weight in the stern. What do you guys think?